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Purpose To compare the diagnostic performance of 18F-fluorodeoxyglucose-PET/MRI and MRI in the diagnosis of pelvic recurrence of rectal cancer. Methods All PET/MRIs of patients in the follow-up of rectal cancer performed between 2011 and 2018 at our institution were retrospectively reviewed. Recurrence was confirmed/excluded either by histopathology or imaging follow-up (> 4 months). Four groups of readers (groups 1/2: one radiologist each, groups 3/4: one radiologist/one nuclear medicine physician) independently interpreted MRI and PET/MRI. The likelihood of recurrence was scored on a 5-point-scale. Inter-reader agreement, sensitivity, specificity, PPV/NPV and accuracy were assessed. ROC curve analyses were performed. Results Fourty-one PET/MRIs of 40 patients (mean 61 years ± 10.9; 11 women, 29 men) were included. Sensitivity of PET/MRI in detecting recurrence was 94%, specificity 88%, PPV/NPV 97% and 78%, accuracy 93%. Sensitivity of MRI was 88%, specificity 75%, PPV/NPV 94% and 60%, accuracy 85%. ROC curve analyses showed an AUC of 0.97 for PET/MRI and 0.92 for MRI, but the difference was not statistically significant (p = 0.116). On MRI more cases were scored as equivocal (12% versus 5%). Inter-reader agreement was substantial for PET/MRI and MRI (0.723 and 0.656, respectively). Conclusion 18F-FDG-PET/MRI and MRI are accurate in the diagnosis of locally recurrent rectal cancer. Sensitivity, specificity, PPV, NPV and accuracy are comparable for both modalities, but PET/MRI increases readers’ confidence levels and reduces the number of equivocal cases. Graphic abstract

Purpose To investigate whether adrenal gland radiodensities alone or set in relation to either the inferior vena cava (IVC) or the spleen can predict hospital mortality in intensive care unit patients. Methods One hundred thirty-three intensive care patients (90 males, age: 66.3 ± 14.5 years) with an acute clinical deterioration were included in this retrospective analysis. CT attenuation (Hounsfield units) of adrenal glands, IVC, and spleen was evaluated by 2 radiologists separately. Adrenal-to-IVC and adrenal-to-spleen ratios were calculated. Receiver operating characteristic (ROC) analysis, combined with the Matthews correlation coefficient (MCC) as a classifier, was used to assess which parameter is the most suitable for short-term, intermediate-term, and overall mortality prediction. Interrater agreement was assessed using intraclass correlation coefficient (ICC). Results The highest discriminative power to distinguish between deceased and survivors was found for the adrenal gland-to-spleen ratio for the 72-h mortality. A threshold of > 1.4 predicted 72-h mortality with a sensitivity of 79.31% and a specificity of 98.08% (area und the curve (AUC) = 0.94; p Conclusions To conclude, the adrenal-to-spleen ratio in CT in portal venous phase may serve as an imaged-based predictor for short, intermediate, and overall mortality and as reproducible prognostic marker for patient outcome.

ZusammenfassungDer vorliegende Artikel beschäftigt sich mit der Bedeutung der FDG- und der Hypoxie-PET bei Kopf-Hals-Tumoren. Dabei liegt der Fokus auf den verschiedenen Quantifizierungsmöglichkeiten und deren Wertigkeit für die klinische Routine und Forschung. Die FDG-PET erfordert in der klinischen Routine nicht zwingend eine quantitative Analyse. Demgegenüber ist die ausschließlich qualitative Auswertung der Hypoxie-PET durch den im Vergleich zum FDG deutlich niedrigeren Kontrast, den alle Hypoxietracer gemein haben, erschwert.Dem Nachteil des niedrigeren Kontrastes steht hier die strikt eindimensionale Aufnahme bzw. das Verweilen des Hypoxie-Tracers im hypoxischen Gewebe gegenüber, ein eindeutiger Vorteil im Vergleich zum Hochkontrast-Tracer FDG, dessen Aufnahme in Tumorzellen multifaktoriell ist.Es gibt eine Vielzahl quantitativer Parameter, die weit über den scheinbar omnipräsenten, aber keinesfalls unumstrittenen maximalen Standardized uptake value (SUVmax) hinausgehen. Deren Erfordernis und ihr Einfluss auf die klinische Routinediagnostik werden dargestellt und kritisch abgewogen.

Background The analysis aimed to compare the radiotracers [68Ga]-Ga-PSMA-11 and [18F]-F-PSMA-1007 intraindividually in terms of malignant lesions, mi(molecular-imaging)TNM staging and presumable unspecific lesions retrospectively as used in routine clinical practice. Methods A retrospective analysis of 46 prostate cancer patients (median age: 71 years) who underwent consecutive [68Ga]-Ga-PSMA-11- and [18F]-F-PSMA-1007-PET/CT or PET/MRI within a mean of 12 ± 8.0 days was performed. MiTNM staging was performed in both studies by two nuclear medicine physicians who were blinded to the results of the other tracer. After intradisciplinary and interdisciplinary consensus with two radiologists was reached, differences in both malignant and presumable nonspecific tracer accumulation were analyzed. Results Differences in terms of miTNM stages in both studies occurred in nine of the 46 patients (19.6%). The miT stages differed in five patients (10.9%), the miN stages differed in three patients (6.5%), and different miM stages occurred only in one patient who was upstaged in [18F]-F-PSMA-1007 PET. Concordant miTNM stages were obtained in 37 patients (80.4%). There was no significant difference between [18F]-F-PSMA-1007 and [68Ga]-Ga-PSMA-11 in the SUVmax locally (31.5 vs. 32.7; p = 0.658), in lymph node metastases (28.9 vs. 24.9; p = 0.30) or in bone metastases (22.9 vs. 27.6; p = 0.286). In [18F]-F-PSMA-1007 PET, more patients featured presumable unspecific uptake in the lymph nodes (52.2% vs. 28.3%; p: p p 18F]-F-PSMA-1007-positive lesions mainly occurred in the ribs (58.7%), axillary lymph nodes (39.1%) and cervical ganglia (28.3%). Conclusion In terms of miTNM staging, both tracers appeared widely exchangeable, as no tracer relevantly outperformed the other. The differences between the two tracers were far more common in presumable unspecific lesions than in malignant spots. A routinely performed two-tracer study could not be shown to be superior. Since it seems at least challenging for most nuclear medicine departments to provide both [18F]-F-PSMA-1007 and [68Ga]-Ga-PSMA-11, it appears reasonable to choose the PSMA radiotracer depending on local availability with attention to the greater occurrence of nonspecific bone findings with [18F]-F-PSMA-1007.

Purpose To develop a new probe for the αvβ6-integrin and assess its potential for PET imaging of carcinomas. Methods Ga-68-Trivehexin was synthesized by trimerization of the optimized αvβ6-integrin selective cyclic nonapeptide Tyr2 (sequence: c[YRGDLAYp(NMe)K]) on the TRAP chelator core, followed by automated labeling with Ga-68. The tracer was characterized by ELISA for activities towards integrin subtypes αvβ6, αvβ8, αvβ3, and α5β1, as well as by cell binding assays on H2009 (αvβ6-positive) and MDA-MB-231 (αvβ6-negative) cells. SCID-mice bearing subcutaneous xenografts of the same cell lines were used for dynamic (90 min) and static (75 min p.i.) µPET imaging, as well as for biodistribution (90 min p.i.). Structure–activity-relationships were established by comparison with the predecessor compound Ga-68-TRAP(AvB6)3. Ga-68-Trivehexin was tested for in-human PET/CT imaging of HNSCC, parotideal adenocarcinoma, and metastatic PDAC. Results Ga-68-Trivehexin showed a high αvβ6-integrin affinity (IC50 = 0.047 nM), selectivity over other subtypes (IC50-based factors: αvβ8, 131; αvβ3, 57; α5β1, 468), blockable uptake in H2009 cells, and negligible uptake in MDA-MB-231 cells. Biodistribution and preclinical PET imaging confirmed a high target-specific uptake in tumor and a low non-specific uptake in other organs and tissues except the excretory organs (kidneys and urinary bladder). Preclinical PET corresponded well to in-human results, showing high and persistent uptake in metastatic PDAC and HNSCC (SUVmax = 10–13) as well as in kidneys/urine. Ga-68-Trivehexin enabled PET/CT imaging of small PDAC metastases and showed high uptake in HNSCC but not in tumor-associated inflammation. Conclusions Ga-68-Trivehexin is a valuable probe for imaging of αvβ6-integrin expression in human cancers.

Background The analysis aimed to compare the radiotracers [68Ga]-Ga-PSMA-11 and [18F]-F-PSMA-1007 intraindividually in terms of malignant lesions, mi(molecular-imaging)TNM staging and presumable unspecific lesions retrospectively as used in routine clinical practice. Methods A retrospective analysis of 46 prostate cancer patients (median age: 71 years) who underwent consecutive [68Ga]-Ga-PSMA-11- and [18F]-F-PSMA-1007-PET/CT or PET/MRI within a mean of 12 ± 8.0 days was performed. MiTNM staging was performed in both studies by two nuclear medicine physicians who were blinded to the results of the other tracer. After intradisciplinary and interdisciplinary consensus with two radiologists was reached, differences in both malignant and presumable nonspecific tracer accumulation were analyzed. Results Differences in terms of miTNM stages in both studies occurred in nine of the 46 patients (19.6%). The miT stages differed in five patients (10.9%), the miN stages differed in three patients (6.5%), and different miM stages occurred only in one patient who was upstaged in [18F]-F-PSMA-1007 PET. Concordant miTNM stages were obtained in 37 patients (80.4%). There was no significant difference between [18F]-F-PSMA-1007 and [68Ga]-Ga-PSMA-11 in the SUVmax locally (31.5 vs. 32.7; p = 0.658), in lymph node metastases (28.9 vs. 24.9; p = 0.30) or in bone metastases (22.9 vs. 27.6; p = 0.286). In [18F]-F-PSMA-1007 PET, more patients featured presumable unspecific uptake in the lymph nodes (52.2% vs. 28.3%; p

New protocols for coronary computed tomography angiography (CCTA) could lower the radiation dose for patients but influence the image quality. To compare image quality and radiation exposure in step-and-shoot CCTA and high-pitch spiral CCTA. Fifty-nine pairs of patients matched for weight, height, sex and heart rate were included in this study (74 m, 44 f, average age 60 years, age range 29–94 years). Step-and-shoot CCTA and high-pitch spiral CCTA was performed on a third generation dual-source CT in equally sized patient groups. The signal-to-noise ratio (SNR) in the ascending aorta and the coronary arteries were determined for each dataset. Image quality was rated using a five-point scale. We used the t-test for paired samples to compare SNR and effective dose, and the Wilcoxon test to compare image quality scores. Mean effective dose for the step-and-shoot protocol (4.15 ± 3.07 mSv) was significantly higher in comparison to the high-pitch spiral protocol (1.2 ± 0.69 mSv; p

Schallwellen mit einer Frequenz zwischen 16 kHz und 1 GHz (diagnostisch gebrauchlich sind Frequenzen zwischen 3 und 10 MHz) werden von einem Sender durch Materie gesandt, regen die Materie zu Schwingungen an und werden an Grenzflachen (Dichteunterschiede) anteilig reflektiert („Echo“; wird von einem Empfanger detektiert und in ein Bildsignal umgewandelt).

Retrospective analysis of all patients with in-hospital cardiac arrest and return of spontaneous circulation (ROSC) in the ICU of the cardiologic department of the University Hospital of Halle (Saale) between 1999 and 2009.During the observation period, 169 patients with in-hospital cardiac arrest and information regarding temperature measurements were treated. Invasive therapeutic temperature management (TTM+) was applied in 64 patients (37.9%), while 105 patients (62.1%) underwent no therapeutic temperature management (TTM-). TTM+ and TTM- showed no relevant differences regarding patient age (TTM+: 67.6 ± 12.6 years; TTM-: 69.8 ± 12.6 years; p = 0.257), comorbidities and the initial rhythm; however, there were more men in the TTM+ group (76.6% vs. 58.1%; p = 0.015). All patients had been intubated. Time until ROSC in TTM+ was significantly longer (25.9 ± 25.8 min vs. 15.0 ± 12.4 min; p 0.005). TTM+ resulted in a lower 30-day survival and an unfavourable neurologic outcome (Glasgow outcome scale I or II: 75% TTM+ vs. 55.2% TTM-). This negative effect persisted after adjustment for age of the patients, but not after adjustment for age and duration of reanimation (nonadjusted odds ratio for adverse neurologic outcome under TTM+: 0.411 (p = 0.011); odds ratio after adjusting for age: 0.361 (p = 0.09); odds ratio after adjusting for age and duration of the reanimation: 0.505 (p = 0.121)).METHODE: Retrospektive Analyse von allen Patienten nach stattgehabtem intrahospitalem Herz-Kreislauf-Stillstand und Wiedererlangung eines Spontankreislaufs, die auf der Intensivstation der kardiologischen Abteilung des Universitätsklinikums Halle (Saale) im Zeitraum von 1999–2009 behandelt werden.Im Untersuchungszeitraum werden insgesamt 169 Patienten (62,4 %) mit Angaben zur Körpertemperatur über mehr als 8 h behandelt. Bei 64 Patienten (37,9 %) wird ein invasives therapeutisches Temperaturmanagement (targeted temperature management – TTM+) durchgeführt, bei 105 Patienten (62,1 %) erfolgt dies nicht (TTM−). Die beiden Gruppen zeigen hinsichtlich des Alters (TTM+: 67,6 ± 12,6 Jahre, TTM−: 69,8 ± 12,6 Jahre; p = 0,257), der Komorbiditäten und des Ereignis-EKGs keine signifikanten Unterschiede, allerdings ist der Anteil männlicher Patienten in der Gruppe TTM+ signifikant größer (76,6 % vs. 58,1 %; p = 0,015). Alle Patienten sind nach der Reanimation intubiert und beatmet. Die Zeit bis zum Wiederkehr eines Spontankreislaufs (ROSC) ist in der Gruppe der TTM(+)-Patienten erhöht (25,9 ± 25,8 min vs. 15,0 ± 12,4 min; p = 0,005). In der Gruppe TTM+ zeigen sich ein geringeres 30-Tage-Überleben sowie ein ungünstigeres neurologisches Ergebnis im Vergleich zur Gruppe TTM− (Glasgow Outcome Scale I oder II: 75 % vs. 55,2 %). Der negative Einfluss der Hypothermie bleibt nach Adjustierung für das Alter der Patienten bestehen, nicht jedoch nach Adjustierung sowohl für das Alter als auch für die Dauer der Reanimation (nichtadjustierte Odds-Ratio für günstiges neurologisches Ergebnis unter TTM: 0,411 [p = 0,011]; Odds-Ratio bei Adjustierung für das Alter: 0,396 [p = 0,009]; Odds-Ratio nach Adjustierung für Alter und Dauer der Reanimation: 0,505 [p = 0,121]).

An 81-year-old man received androgen deprivation therapy for a locally advanced prostate cancer and, 6 months later, a curative radiation therapy. Half a year later, the patient presented with a steeply increased PSA value (32 ng/mL) and a suppressed testosterone level (0.48 nmol/L). The consecutively performed 68Ga-PSMA PET/CT revealed, besides local tumor remains and several PSMA-positive lymph node and soft tissue metastases, an extensive, diffuse PSMA ligand accumulation in the omentum, which was immunohistochemically proven to be a carcinomatosis of prostate cancer. None of the extraprostatic lesions were present in the pretherapeutic PSMA PET 1 year ago.

Background The functional 6-[18F]FDOPA positron emission tomography (PET) can be a helpful tool in differentiating parkinsonism with dopaminergic deficiency from clinically similar differential diagnoses. Furthermore, in T2*/susceptibility-weighted imaging (SWI) magnetic resonance imaging (MRI) sequences the structural integrity of the Nigrosome 1 (N1) can be assessed by checking the presence of the swallow tail sign (STS). We therefore retrospectively compared the performance of the 6-[18F]FDOPA PET with the N1 detection in patients suspected with parkinsonian diseases. Forty-three consecutive patients (m: 23, f: 20, mean age: 63 ± 12 years) were included in the study. They underwent clinically indicated 6-[18F]FDOPA PET/MRI scans as part of their neurological evaluation of uncertain parkinsonian syndromes. Visual and semi-quantitative PET imaging results were statistically compared with visual N1 assessment on 3 T SWI. As the gold standard, we defined the clinical diagnosis at the last follow-up, which included idiopathic Parkinson syndrome (IPS; n = 18), atypical parkinsonian syndromes (APS; n = 9) and other neurological diseases without dopaminergic deficit (n = 16). Results Thirty-five of 43 patients (81%, Kappa 0.611) had corresponding results in 6-[18F]FDOPA PET and SWI. Seven of the remaining 8 patients were correctly diagnosed by 6-[18F]FDOPA PET alone. Sensitivity, specificity and accuracy for 6-[18F]FDOPA and N1 imaging were 93%, 94%, 93% and 82%, 75%, 79%, respectively. Conclusions 6-[18F]FDOPA PET and Nigrosome 1 evaluation had an overall good intermodality agreement. Diagnostic agreement was very good in cases of clinically suspected idiopathic Parkinson syndrome and fair in atypical parkinsonian syndromes, but poor in patients with non-parkinsonian disorders. 6-[18F]FDOPA PET showed higher sensitivity, specificity and accuracy in discriminating parkinsonian syndromes from non-parkinsonian disorders than the N1 evaluation. In summary, the additional benefit of N1 assessment in patients with APS or parkinsonism without dopaminergic deficit needs to be proven by prospective studies.

Purpose: The study aimed to evaluate the effect of androgen deprivation therapy (ADT) on PSMA imaging and its correlation to the PSA concentration comparing qualitative and quantitative parameters: SUVmax, SUVmean, PSMA-derived tumor volume (PSMA-TV), total lesion PSMA (TL-PSMA) and metabolic imaging (mi)PSMA score. Methods: Retrospective analysis of 19 therapy-naïve and oligometastatic prostate cancer patients (median age 73 years) who underwent either 68Ga-PSMA-11-PET/CT or -PET/MRI before initiation (T1) of as well as during ADT (T2). The median duration of ADT was 156 days (range: 61-289 days). All lesions were analyzed using several qualitative and quantitative PET parameters.Results: During long term ADT occurred a relevant decrease of lesion count and PSMA expression. A total of 104 PSMA-positive lesions (21 intraprostatic, 54 lymphonodal, 29 osseous) were visually detected at each of the two points, while at T2 two new bone lesions were detected in one patient. All analyzed PET parameters, which correlated strongly with each other. During ADT, all patients experienced a decrease of their PSA level (median: 29.1 before vs. 0.69 after; pConclusion: Post ADT scans detected less PSMA-positive lesions with overall lower PSMA expression, regardless of primary tumor site or metastatic sites. None of the PET parameters has proven to be superior, as they all correlated modestly with the PSA value at T2. Thus, the simply acquirable miPSMA score seems to be the most suitable for evaluating the effect of ADT on PSMA expression.

To investigate whether adrenal gland radiodensities alone or compared to the inferior vena cava (IVC) can correctly predict hospital mortality in patients in intensive care.One hundred thirteen intensive care patients (76 males, age: 67.2 ± 14.0 years) with an acute clinical deterioration were included in this retrospective analysis. For the venous and the arterial phase CT attenuation (Hounsfield units) of adrenal glands and IVC was ROI-based evaluated by two radiologists separately. ROC analysis, combined with the Matthews Correlation Coefficient (MCC) as a classifier, was used to assess whether one of the parameters is suitable for predicting short and medium-term mortality and, if so, which parameter is most appropriate. Interrater agreement was assessed using the intraclass correlation coefficient.Twenty-one patients (18.6%) died within three days in the ICU. Measurements of the adrenal glands in the portal venous phase yielded the highest discriminative power (=AUC) to distinguish between deceased and survivors. A threshold ratio of95.5 predicted 72-hour mortality with a sensitivity of 76.19% and a specificity of 92.39% (AUC = 0.84; p 0.0001). The positive likelihood ratio was 10.1; the positive predictive value was 69%. The predictive power for 24-hour mortality was slightly lower. Venous adrenal-to-IVC ratios and arterial measurements as a whole were substantially less suitable. All intraclass correlation coefficients indicated a high interrater agreement.In the portal venous phase, hyperattenuating of the adrenal glands on contrast-enhanced CT can predict short and intermediate ICU mortality quite well and may serve as a reproducible prognostic marker for individual patient outcomes.

An 80-year-old man developed high-risk prostate cancer after 7 years of active surveillance. For staging and treatment planning, a Ga-PSMA PET/MRI was performed. Besides the PSMA-positive primary tumor and a solitary bone metastasis in the fifth thoracic vertebral body, an intensive intrahepatic PSMA expression (SUVmax, 16.3) was suspicious for a liver metastasis. The results of a previously performed contrast-enhanced CT, a consecutively performed contrast-enhanced ultrasound, and a follow-up PSMA PET/CT after 4 months with a stable lesion during androgen deprivation lead to the diagnosis of a vascular malformation metabolically mimicking a hepatic metastasis of the prostate tumor.

A 65-year-old woman with a long history of metastasized, highly differentiated (G1) neuroendocrine tumor of pancreatic origin presented for follow-up Ga-DOTATATE PET/CT after 7 peptide receptor radiotherapies. In the previous scan, she already had discrete intracranial tracer accumulations, which were massively progressive in the recent Ga-DOTATATE PET/CT 8 months later. This case illustrates that cerebral metastases in neuroendocrine tumors may occur many years after initial diagnosis, and their somatostatin receptor expression may rise within a few months to a level that reasonably justifies further peptide receptor radiotherapy.

Aim 68Ga-PSMA-11 is the gold standard for molecular imaging of prostate cancer. However, recurrent tumor manifestations or metastases cannot be detected in every case. Therefore, we investigated if there is an additive value of the gastrin-releasing peptide receptor (GRP-R) ligand 68Ga-RM2 compared to the well-established 68Ga-PSMA-11 in patients with (Group 1) and without (Group 2) pathologic PSMA-expression in different tumor stages. Patients and Methods Sixteen men (median age: 74 years, range 50–80 years) with prostate cancer in different stages who had a recent negative (n = 8) or pathologic (n = 8) PSMA PET underwent a subsequent 68Ga-RM2 PET. Both examinations were analyzed qualitatively and quantitatively and compared in terms of pathologic and physiologic tracer distribution. Results None of the PSMA-negative patients showed any pathological RM2-accumulation. Pathologic PSMA-uptake was observed in 8 patients of whom 5 had pathologic RM2-uptake. The number of patients with a local recurrence was equal in both scans (n = 3). Bone metastases and lymph node metastases were detected in less patients in RM2 PET compared to PSMA PET (n = 4 vs. 7 and n = 2 vs. 5, respectively). In one patient, PSMA-positive liver metastases were not detected in RM2. RM2 PET revealed two additional lesions indicative for bone metastases in two patients with multiple PSMA-positive bone metastases, which had no therapeutic consequence. Conclusion At least in our small and heterogeneous patient population, 68Ga-RM2 showed no clinically relevant, additional benefit compared to 68Ga-PSMA-11 PET.

Purpose To evaluate the use of diffusion-weighted MRI (DWI) for initial staging of Hodgkin`s lymphoma and compare it to FDG PET. Methods Forty-one patients with Hodgkin`s lymphoma (14 f, 27 m, median age 39 y) were included in this retrospective study. All patients underwent FDG PET/MR for initial staging, including DWI. The Lugano classification was used to describe disease extent. A combination of follow-up imaging and histopathology served as the reference standard. Method agreement was assessed using weighted kappa (κ). The accuracy of the imaging methods was evaluated using ROC curve analysis. Results Regarding the Lugano stage, DWI and FDG PET had identical results in 34/41 cases (κ = 0.77). Sensitivity and specificity for nodal involvement was 89.9% and 93.8% for DWI, and 93.8% and 86.9% for FDG PET, respectively. In regard to extranodal involvement, sensitivity and specificity were 88.5% and 99.3% for DWI and 92.3% and 92.7% for FDG PET. The accuracy of both methods for nodal (p = 0.06) and extranodal involvement (p = 0.66) did not differ significantly. Conclusion Despite high sensitivity and specificity, DWI in free breathing cannot be currently recommended as an alternative to FDG PET in initial staging of Hodgkin`s lymphoma due to substantial differences in regard to therapy-determining Lugano Stage.

Retrospective evaluation of serial FDG-PET/CT scans in head and neck squamous cell cancer (HNSCC) patient's follow-up after primary radiochemotherapy (RCTx), to assess the diagnostic accuracy of an experienced observer vs. an objective classification compared to standard clinical follow-up examinations.Sixty-nine patients with locally advanced HNSCC were included, who received curative RCTx. Follow-up included serial FDG-PET/CT at the following time intervals t1: ≤ 270 d, t2: 271-540 d, t3: 540 d after curative RCTx. The likelihood to detect local recurrences, nodal and distant metastases were compared between (i) experienced observer, (ii) an objective classification system by Zundel et al. 25, and (iii) routine clinical follow-up examinations.Twenty-two local recurrences, 7 nodal and 17 distant metastases were recorded during the follow-up. The diagnostic accuracy for local recurrence of the experienced observer vs. objective classification was 78 % vs. 77 % for t1, 83 % vs. 79 % for t2 and 100 % vs. 84 % for t3.The classification (ii) and the conventional follow-up (iii) resulted in a relatively high amount of equivocal findings reducing the diagnostic accuracy.Evaluation of FDG-PET/CT by an experienced observer in follow-up of HNSCC patients after curative RCTx resulted in the highest diagnostic accuracy in comparison to an objective classification and to routine clinical examination.HNSCC is a malignant tumor with a high likelihood of recurrence, especially in the first two years after curative RCTx. Early detection of recurrence is of high clinical importance, since there are several effective second line therapies that may have curative potential in some patients.ZIEL: Retrospektive Analyse der FDG-PET/CT in der Nachsorge von Patienten mit primär radiochemotherapierten zervikalen Plattenepithelkarzinomen (HNSCC). Vergleich der diagnostischen Genauigkeit des erfahrenen Befunders mit einem objektiven Klassifizierungssystem und mit der klinischen Nachsorgeuntersuchung.69 Patienten, die wegen eines lokal fortgeschrittenen HNSCC eine kurative Radiochemotherapie (RCTx) erhielten, wurden eingeschlossen. Die Nachsorge umfasste serielle FDG-PET/CT nach RCTx zu folgenden Zeitintervallen t1: ≤ 270 d, t2: 271–540 d, t3: 540 d. Die Detektionsraten von Lokalrezidiven, Lymphknoten- und Fernmetastasen durch den erfahrenen Befunder (i), das objektive Klassifikationsverfahren (ii) nach Zundel 25 sowie durch die routinemäßige klinische Nachsorge (iii) wurden verglichen.Insgesamt wurden 22 Patienten mit Lokalrezidiven, 7 mit Lymphknoten-, und 17 mit Fernmetastasen detektiert. Die diagnostischen Genauigkeiten des erfahrenen Untersuchers (i) und des objektiven Klassifizierungssystems (ii) bezüglich der Lokalrezidive betrugen 78 % und 77 % zu t1, 83 % bzw. 79 % zu t2 und 100 % bzw. 84 % zu t3. Das Klassifizierungssystem nach Zundel, aber auch die konventionelle Nachsorgeuntersuchung führte zu einem relativ hohen Anteil uneindeutiger Befunde, was sich negativ auf die diagnostische Genauigkeit auswirkte.Die Auswertung der FDG-PET/CT bei Patienten mit lokal fortgeschrittenen HNSCC nach kurativer RCTx durch den erfahrenen Befunder hat die höchste diagnostische Genauigkeit für die Detektion von Lokalrezidiven und/oder Metastasen im Vergleich zu einem objektiven Klassifizierungssystem und der routinemäßigen klinischen Nachsorge.Vor dem Hintergrund zahlreicher effektiver Zweitlinientherapien mit teils kurativem Potenzial und der hohen Rezidivneigung in den ersten beiden Jahren nach Primärtherapie ist die frühzeitige und exakte Detektion von Rezidiven und Metastasen bei HNSCC-Patienten von großer Bedeutung.

Regardless of its high positron energy

Regardless of its high positron energy, 68 Ga-labeled PSMA ligands have become standard of care in metabolic prostate cancer imaging. 64 Cu, a radionuclide with a much longer half-life (12.7 h), is available for PSMA labeling allowing imaging much later than 68 Ga. In this study, the diagnostic performance of 64 Cu-labeled PSMA was compared between early and late scans. Sixteen men (median age: 70 y) with prostate cancer in different stages underwent 64 Cu-PSMA-617-PET/CT 2 and 22 hours post tracer injection. Pathologic and physiologic uptakes were analyzed for both points of time. Pathologic tracer accumulations occurred in 12 patients. Five patients presented with pathologic uptake in 17 different lymph nodes, two patients showed pathologic bone uptake in nine lesions, and seven patients had pathologic PSMA uptake in eight prostatic lesions. Physiologic uptake of the renal parenchyma, urine bladder, and salivary glands decreased over time, while the physiologic uptake of liver and bowel increased. In the present study, 64 Cu-PSMA-617-PET demonstrated to be feasible for imaging prostate cancer for both the primary tumor site and metastases. Later imaging showed no additional, clinically relevant benefit compared with the early scans. At least the investigated time points we chose did not vindicate the additional expenditure.

Purpose To assess the type and frequency of vascular changes in the superior mesenteric artery (SMA) associated with the hypovolemic shock complex (HSC). Methods Twenty-six patients (14 males, 70.6 ± 11.2 years) meeting the criteria for hypovolemic shock complex in computed tomography were examined for the presence of angiographic signs of non-occlusive mesenteric ischemia (NOMI) in the SMA: the string of sausages sign and spasms of the arcades of mesenteric arteries on coronal maximum intensity projection images (MIP). Interrater agreement was assessed using weighted kappa (κ). Results Vascular changes of the SMA were visible in almost all of the patients with HSC with a frequency of 88.5 %–96.2 %. Intraclass correlation coefficients indicated a substantial to almost perfect interrater agreement. Conclusions Using computed tomography, it is possible to reliably and reproducibly detect vascular changes in SMA known from angiography in the context of hypoperfusion. The pathological vascular changes also occur more frequently than other classic signs of a CT hypoperfusion complex. Since the qualitative assessment of the SMA requires only a small amount of time, it is suitable as a further criterion for the presence of the CT hypoperfusion complex.

A 68-year-old woman who underwent a thyroidectomy for bilateral goiter 20 years ago was referred to our department. The examination revealed a newly occurred thyroid nodule in the right central lobe. Unexpectedly the Tc-pertechnetate scan revealed several extrathyroidal foci right-sided supraclavicular, beside a cold thyroid nodule in the right lower lobe. Consecutive surgery and histology confirmed the suspected diagnosis of follicular thyroid cancer with multiple bone metastases. Whole-body scintigraphy performed after the following radioiodine therapy indicated disseminated osseous metastases.

A 79-year old man with prostate cancer under active surveillance for 5 years was referred for a PSMA-PET/MRI for re-evaluation because of a rising prostate-specific antigen value. PET/MRI revealed a ribbonlike tracer accumulation in a healing fracture of the distal radius. This case illustrates that PSMA expression may occur in healing bone fractures in the distal radius. It can be assumed that benign causes of tracer accumulations in the upper extremities are missed in PET/CT due to elevated position of the arms during image acquisition.